Viral Unit. The purpose of the Viral Unit will be to provide services and expertise in virus vector gene transfer and expression to enhance the capabilities of new and established investigators conducting digestive diseases research. The Unit will centralize and make available innovative uses of powerful genetic manipulation technologies that otherwise would not be broadly accessible. By providing and maintaining the high cost equipment required for this technology, the Unit will avoid redundancy in equipment purchases and facilitate and broaden the research capabilities of all investigators. Because the use of lentiviral vectors as tools for enhancing studies of digestive diseases is not yet common practice, the integration of this technology and expertise into the UAB DDRDC is a unique strength of the application. Bacterial Unit. The purpose of the Bacterial Unit will be to acquire and characterize defined commensal bacteria and/or their recombinant products for use by members of the Center. The Unit will facilitate standardization of such bacteria for in vitro and in vivo systems. As the source of genetically-defined [sic] or genetically-manipulated [sic] bacteria to be used for colonization of germ-free animal, the Unit will be highly complimentary to the Gnotobiotic Unit of Core 3. In addition, the Unit will provide bacterial 16S rDNA analysis to characterize and provide quality control of defined organisms. Such analysis will be a useful check that Gnotobiotic mice with a defined flora are colonized only with the organisms intended. This method does not require culture and thus is ideal for analysis of enteric bacteria, many of which have never been cultured and are thought to be unculturable. The use of standardized genetically-defined [sic] strains across multiple experimental systems, both in vitro and in vivo, will allow Center investigators to build data sets that can be compared and assembled into a larger context of understanding. For example, the effects of defined organisms or their products on epithelial ceils or lymphocytes in vitro could be compared to the effect of the organism in vivo. The Core will provide a variety of services listed below that will not only be cost efficient, but will also facilitate pilot studies by Center investigators and other interested investigators to expand research in this area.